MILWAUKEE, Wisconsin (AP) -- A university instructor who came under scrutiny for arguing that the U.S. government orchestrated the September 11 attacks likens President Bush to Adolf Hitler in an essay his students are being required to buy for his course.

The essay by Kevin Barrett, "Interpreting the Unspeakable: The Myth of 9/11," is part of a $20 book of essays by 15 authors, according to an unedited copy first obtained by WKOW-TV in Madison and later by The Associated Press.

The book's title is "9/11 and American Empire: Muslims, Jews, and Christians Speak Out." It is on the syllabus for Barrett's course at the University of Wisconsin-Madison, "Islam: Religion and Culture," but only three of the essays are required reading, not including Barrett's essay.

Barrett, a part-time instructor who holds a doctorate in African languages and literature and folklore from UW-Madison, is active in a group called Scholars for 9/11 Truth. The group's members say U.S. officials, not al-Qaida terrorists, were behind the attacks on the World Trade Center and the Pentagon on September 11, 2001.

"Like Bush and the neocons, Hitler and the Nazis inaugurated their new era by destroying an architectural monument and blaming its destruction on their designated enemies," he wrote.